The Role of Circadian Rhythm Disruption in the Development of Colorectal Cancer: A Literature Review

Rates of early-onset colorectal cancer (CRC) have increased among adults under age 50, encouraging interest in environmental and lifestyle factors that may contribute to CRC more broadly. One emerging area of interest is disruption of the circadian rhythm, the body’s internal biological clock. Modern lifestyles can interfere with normal circadian function, potentially affecting biological processes involved in maintaining cellular health. This review examines current evidence connecting circadian rhythm disruption with colorectal cancer, with particular attention to lifestyle-related circadian disturbances and the biological changes that may contribute to colorectal carcinogenesis. Most of the evidence reviewed is not specific to early-onset disease, and the extent to which circadian disruption contributes to the rising incidence of CRC in younger adults remains unknown. Existing research suggests that chronic circadian disruption may influence pathways involved in normal cellular regulation and tumor development, although the relationship remains complex and continues to be investigated. Because circadian rhythm is influenced by modifiable behaviors and environmental exposures, understanding this relationship may provide new opportunities for colorectal cancer prevention. Further research, particularly longterm studies in younger populations, is needed to determine whether circadian disruption specifically contributes to early onset colorectal cancer and whether interventions that support healthy circadian rhythms may help reduce risk.